Look for threads titled [IR] or [Ebony]. IR will have interracial stuff, perhaps mostly black guys and white girls, but also some white on black too. Ebony will have nothing but black girls, so lots of white on black and some black on black.

You can sort the whole subforum by these tags by sorting alphabetically. See the EL rules thread for how to do this.

Last, check out the EL Index, which will link you to Black hotties in other sections, where you can find more white on black